The son of a Hawaiian doctor testified against him, saying that his father confessed to trying to kill his stepmother.
Gerhardt Koenig was charged with attempted second-degree murder. The anesthesiologist is accused of hitting his wife, Ariel Koenig, with a rock on Pali Puka Road on Oahu on March 24, 2025. He has pleaded not guilty.
Emil Koenig took his stand on Tuesday, saying that minutes after the alleged attack, his father called him and confessed.
“What did the defendant say to you during that call, as closely as you can remember word for word?” Prosecutor Joel Garner said.
“That he wouldn’t go back to Maui and take good care of the little kids and that he had – that Ari, my stepmother, was cheating on him and that he tried to kill her,” Emil Koenig responded.
Prosecutors allege that Dr. Koenig first tried to push his wife, Ariel, off a cliff in Hawaii, tried to inject her with an injection, before repeatedly smashing her head with a jagged rock.
“I asked him what was on his shirt, because it looked like I saw stains of something on his shirt, and he said, ‘It’s just her,’ Ari’s blood,” Emil Koenig testified.
A pair of hikers say they found the couple with Ariel covered in blood.
Related | Doctor’s wife stands trial for alleged murder conspiracy in Hawaii
An hour later – Emil received another video call from his father – whom Emil referred to in court only as “the defendant”.
“He asked me if I had told anyone and I said yes and I told him who I told, and then – he said he was going to jump and he said that several times,” Emil Koenig said.
He said that the second call ended with his father saying: “I will go before the police arrest me.”
Dr. Koenig’s defense team says Ariel first attacked him after he confronted her about an affair, and they say he hit her with the rock in self-defense.
While questioning Emil, they pointed out that there were some parts of the calls that he couldn’t remember.
Prosecutor Joel Garner then asked: “Is there any doubt in your mind that the defendant told you he tried to kill Ariel?”
“No,” Emil König replied.
The big question now is whether Dr. Koenig will take the stand in his own defense.
ABC News contributed to this report.
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